Since the anticancer properties of delta 9-THC have been established in mice, several important questions remain. What is the mechanism of this response? Are there any other DNA related functions which are effected by delta 9-THC? Do these mechanisms have any relation to the C.N.S. effects of delta 9-THC? In order to approach these questions in vivo and in vitro on spleen, C3H-mammary tumor, Lewis lung, and regenerating liver DNA polymerase will be determined. This will be refined to quantitation of DNA chain initiation and propagation. The incidence of double and single strand breaks caused by delta 9-THC in vivo will also be determined. The effects of delta 9-THC on aminopyrine demethylase enzyme induction by phenobarbital and tyrosine- transaminase by hydrocortisone or typtophan will indicate whether RNA and protein synthesis are involved in this response. Both nuclear and nucleolar TNA polymerase will be studied and purified DNA from delta 9- THC treated mice will be assayed for template activity. Finally, polysomes from delta 9-THC treated mice will be studied as an index of protein synthetic capacity.